1. Field of the Invention
The present invention is generally concerned with fixed printing shaft printing machines of the kind described in published European patent application No. 0260178 filed under application number 87401897.1 on Aug. 18, 1987 corresponding to U.S. Pat. No. 4,782,750 hereby incorporated by reference.
2. Description of the Prior Art
A machine of this kind prints on a substantially cylindrical convex area of an object. It comprises a fixed printing axis, a mobile assembly adapted to carry a flat printing plate or the like, rotation means for rotating an object to be printed about the printing axis in contact with the printing plate or the like, correction means for correcting the distance between the printing axis and the printing plate or the like, a drive shaft and transmission means coupling the rotation means to the drive shaft.
Specifically designed for printing objects with an oblong (usually called "oval") transverse cross-section, a printing machine of this kind can also be used to print objects with a circular transverse cross-section.
However, although pivoting through an angle of 130.degree. is generally sufficient for printing an object with an oblong transverse cross-section, to print an object with a circular transverse cross-section the object has to rotate on itself by significantly more than one revolution.
A general object of the present invention is an arrangement providing a particularly simple way to satisfy this two-fold requirement.